All was pleasant and tranquil at Top Gear Towers until I hooked up my Origin b2 (which I want to have my babies its so good) and realised my speedo is out...
Either that or the b2 is lying to me.
Its around 10mph out, according to the b2 - but, it doesnt feel out...
This is all on feeling, but 50mph feels like 50 - and 80mph feels like 80...
When sitting at 70mph on the clock, I\'m not causing a roadblock on the motorway...
Any advise?
Car has standard alloys, and is a jap import.
R
I thought my speedo was out, eventualy saw a Police radar trap, explained import etc and kindly asked if they\'d gun me.
Most helpful drove towards them at 30 - actual speed 35.4.
Doesn\'t sound much but thats 70 @ 60 etc.
Invested Road Angel, problem solved.
John
QuoteOriginally posted by johnf
I thought my speedo was out, eventualy saw a Police radar trap, explained import etc and kindly asked if they\'d gun me.
Most helpful drove towards them at 30 - actual speed 35.4.
Doesn\'t sound much but thats 70 @ 60 etc.
Invested Road Angel, problem solved.
John
Police helping for once dont get to usd to it
**Edited by Donato**
My origin b2 says my speedo is spot on , I\'d trust the origin rather than your speedo although it is about a second behind
You wont get more accurate than GPS buddy, unless you can do a check like Johnf did with the Police.
Just a bit of hijack too, when can we expect the new series too start and what wonders are we going to be treated too!!!!!
Although surely it\'s down to the calibration of the guys speed gun? It could be out too lol!!:rolleyes:
I\'d trust the GPS as it\'s gonna be the most accurate apart from the lag of signal transfer as said before. Unless you have a mate that can follow you down the road?
Often wondered how out my speedo is as I alwyas seem to fly past cars like there at a standstill!!:confused: ;)
Speedos are designed to err on the safe side - i.e. report a higher speed than actual.
Reasons for it reading lower than you\'re actually travelling are:
- Dodgy kph-mph converter
- circumference of wheels not as designed
Standard 16" wheels are 225/50/16, some models have 17\'s as standard which I think are 235/45/17...
QuoteI thought my speedo was out, eventualy saw a Police radar trap, explained import etc and kindly asked if they\'d gun me.
it shouldnt have passed the SVA then, there is no tolerance for the car doing more than the speedo displays. There is lots the otherway, ie, reading 35 actually doing 30.
With SVA, their calibration only has to be right if your speedo is under reading,
i.e speedo 70, your speed, 73, 74 etc
over readings fine,
i.e speedo 70, your speed 65, 66 etc.
As mentioned above, which way is your speedo reading and have you introduced any mods like the alloys.
Hi Guy\'s
Afew weeks ago l got James ( Blue Adept) to follow me down the road with his Sta Nav to check my spedo because l have a stock 4.1 ratio diff and 19" wheels and big profile tyres and at 70mph and 80 it was 1 mph out !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
These cars must read so far above what your actualy doing it\'s incredable !
It would seem all cars speedos air on the side of caution, even my brothers brand new Vectra is about 5 mph out at 70.
Wow so if I\'m doing 90 I\'m really only doing about 80?? I think I\'ll have to invest in a GPS system at some point.
It\'s reading low - so 80 on the clock, 70 on the b2.
It doesnt feel like its wrong though - I tried driving to the b2 last night, and it seemed far too quick (and I aint no pansy)...
How can i check it - can a garage do it?
Its one of those annoying things now, where I no longer trust the speedo.
you\'ve find nearly all cars in the UK have speedo error of some sort. Our last brand new car read 5mph high at 60, over 100 most speedos at 10% out. I\'ve got a 92 reno & it does actually say 60 @ 60 with a handheld GPS anything below that & its high
I have a big one! erm speedo difference that is..
At the present moment, when the road angel says 70mph my speedo says 130mph...
The only other way you can check is by doing a speed check over a measured mile, run at 70, 80 whatever, time the run on a stopwatch and then do the maths, time taken etc etc.
But there is no way i would belive a GPS to be innacurate unless you have a very very poor signal which keeps dropping out.
The Apexi PFC has a speed calculation jobber in it. At 30mph both speedo and PFC read 30mph, but at a speedo indicated 70mph the PFC reads around 66mph.
I\'ve not been faster than that ociffer so can only speculate that the problem seems to get to certain degree of inaccuracy (-5 or -6pmh in may case) and remain there above 70mph.
Would love to know which one\'s actually correct, am inclined to believe the PFC as I guess it works off rpm and some stuff in the gearbox...
H
very interestin thread this....
and it got me to thinking...
if your speedo is reading 70 and you are only doing 66.... does this mean that your milometer is out as well...
are we putting 70 miles on our clocks when we have only travelled 66... those 4 or 5 miles will soon start to add up...
I know it is only 5 miles home from work, but the other day I put on 25 miles... just going home.... somethings askew here... or was it just a nice day for some b road driving... hmmm
Speedo\'s are meant to over read. They are designed to. And the faster you go, the more they\'ll over-read There are 2 reasons for this:
1. It\'s actually very expensive for a manufacturer to produce a 100% accurate speedo.
2. Safety!
I speedo suspected my speedo to be reading kph a while back, so got a mate with GPS to ride along with me and confirm it - which showed it was reading kph. It\'s back to reading mph now!